diff --git a/src/PHPUnit/ApiCheckUserResponse.json b/src/PHPUnit/ApiCheckUserResponse.json
new file mode 100644
index 0000000..81a50fe
--- /dev/null
+++ b/src/PHPUnit/ApiCheckUserResponse.json
@@ -0,0 +1,5 @@
+{
+    "error_msg": "error_Username already exists",
+    "data": "",
+    "error_code": 10003
+}
\ No newline at end of file
diff --git a/src/Response/ApiCheckUserResponse.php b/src/Response/ApiCheckUserResponse.php
new file mode 100644
index 0000000..27b211b
--- /dev/null
+++ b/src/Response/ApiCheckUserResponse.php
@@ -0,0 +1,44 @@
+<?php
+
+namespace NystronSolar\GrowattApi\Response;
+
+use Psr\Http\Message\ResponseInterface;
+
+class ApiCheckUserResponse extends ApiResponse
+{
+    private bool $userExists;
+
+    public function __construct(ResponseInterface $httpResponse, string $errorMessage, int $errorCode, \stdClass $responseJson, bool $userExists)
+    {
+        parent::__construct($httpResponse, $errorMessage, $errorCode, $responseJson);
+
+        $this->userExists = $userExists;
+    }
+
+    public function userExists(): bool
+    {
+        return $this->userExists;
+    }
+
+    public static function generate(ResponseInterface $httpResponse): ApiCheckUserResponse|false
+    {
+        $primitiveApiResponse = parent::generate($httpResponse);
+        if (!$primitiveApiResponse) {
+            return false;
+        }
+
+        $responseJson = $primitiveApiResponse->getResponseJson();
+        $errorMessage = $primitiveApiResponse->getErrorMessage();
+        $errorCode = $primitiveApiResponse->getErrorCode();
+
+        $userExists = 10003 === $errorCode ? true : false;
+
+        return new ApiCheckUserResponse(
+            $httpResponse,
+            $errorMessage,
+            $errorCode,
+            $responseJson,
+            $userExists
+        );
+    }
+}
diff --git a/src/Route/ApiCheckUserRoute.php b/src/Route/ApiCheckUserRoute.php
new file mode 100644
index 0000000..39973dd
--- /dev/null
+++ b/src/Route/ApiCheckUserRoute.php
@@ -0,0 +1,50 @@
+<?php
+
+namespace NystronSolar\GrowattApi\Route;
+
+use NystronSolar\GrowattApi\Response\ApiCheckUserResponse;
+
+final class ApiCheckUserRoute extends ApiRoute
+{
+    private string $userName;
+
+    public function __construct(string $userName)
+    {
+        $this->userName = $userName;
+    }
+
+    public function getUserName(): string
+    {
+        return $this->userName;
+    }
+
+    public static function getDescription(): string
+    {
+        return 'Check if the User Name already exists';
+    }
+
+    public static function getRequestRoute(): string
+    {
+        return 'user/check_user';
+    }
+
+    public static function getRequestMethod(): string
+    {
+        return 'POST';
+    }
+
+    /**
+     * @return class-string<ApiCheckUserResponse>
+     */
+    public static function getApiResponse(): string
+    {
+        return ApiCheckUserResponse::class;
+    }
+
+    public function getAllParams(): array
+    {
+        return [
+            'user_name' => $this->getUserName(),
+        ];
+    }
+}
diff --git a/tests/Response/ApiCheckUserResponse.php b/tests/Response/ApiCheckUserResponse.php
new file mode 100644
index 0000000..55e7ac9
--- /dev/null
+++ b/tests/Response/ApiCheckUserResponse.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace NystronSolar\GrowattApiTests\Response;
+
+use NystronSolar\GrowattApi\PHPUnit\GrowattApiTestData;
+use NystronSolar\GrowattApi\Response\ApiCheckUserResponse;
+use NystronSolar\GrowattApi\Route\ApiCheckUserRoute;
+use PHPUnit\Framework\TestCase;
+
+class ApiCheckUserResponseTest extends TestCase
+{
+    use GrowattApiTestData;
+
+    public function testRequest()
+    {
+        $route = new ApiCheckUserRoute('');
+        /** @var ApiCheckUserResponse|false $response */
+        $this->assertNotFalse($response = $this->makeApiClientRequest($route));
+        $this->assertSame('', $response->getErrorMessage());
+        $this->assertSame(0, $response->getErrorCode());
+        $this->assertFalse($response->hasErrors());
+
+        $this->assertFalse($response->userExists());
+    }
+}